The story is set in mid-19th century in Siam, during the King Mongkut Era and at the height of the Rattanakosin Dynasty, when Siam was plagued with wars with its neighbouring kingdoms. Mak (Mario Maurer) was drafted to serve in a war against the foreign invasion, forcing him to leave behind his pregnant wife Nak (Davika Hoorne) at the town of Phra Khanong, not far from Central Bangkok. He was wounded during a battle and sent to a medical camp, where he met Ter, Puak, Shin and Aey, who later became his best friends. Meanwhile, in Phra Khanong, Nak struggled alone painfully to give birth to the baby. Shortly after, villagers in the neighborhood heard her singing lullabies to her baby, causing hair-raising chills and making them cower in fear. Rumours started circulating around the village that Nak had already died in labor and was now a ghost haunting the house.